1. Field of the Invention
This invention relates to a rotatable holder for a halogen lamp, particularly to one that can be threadably connected with a conventional threaded lamp socket to fit a halogen lamp in order to increase its effectiveness and practicability, as well as ease of usage.
2. Description of the Related Art
A halogen lamp is quite different from the prior art threaded lamp. A halogen lamp is shown in FIG. 1. The top of the bulb 101 of the halogen-lamp 10 is provided with a connector 102 having upwardly protruding plus and minus insert lugs 103A, 103B and the lamp 10 is insertable into a lamp socket 20, which includes a cylindrical porcelain shell 201 having two arc-shaped insert grooves 202 for receiving the two insert lugs 103A, 103B of the lamp 10 and to engage therein by turning the lamp 10, to complete the combination of the halogen lamp 10 with the lamp socket 20, as shown in FIG. 3.
More specifically, the cylindrical porcelain shell 201 of the lamp socket 20, as shown in FIG. 4, is provided with two insert grooves 202 and two metal terminals 204 are positioned at outer sides of the two insert grooves 202 and connected with electric wires 203. Two spring members 205 are respectively provided in the insert grooves 202 and elastically contact the metal terminals 204 to push the terminals 204 to face the insert grooves 202. Then, an insulating disc 206 and a connecting frame 207 on the insulating disc 206 are combined with the upper end of the cylindrical porcelain shell 201 by means of rivets 207A. Then, the halogen-lamp 10 is inserted in the lamp socket 20, so that the insert lugs 103 of the halogen lamp 10 and the metal terminals 204 of the lamp socket 20 contact each other to make an electric connection for lighting. In addition, the elasticity of the spring members 205 pushes the metal terminals 204 to tightly clasp the insert lugs 103A, 103B of the halogen lamp 10 to maintain a smooth flow of electric current.
As can be understood from the description above, a special lamp socket 20 is needed for installing a halogen lamp 10. Conventionally, common threaded lamp sockets are installed on a wall and electric wires are hidden inside the walls to maintain an orderly appearance. When a halogen lamp is to be used, the hidden wires have to be found and pulled out to connect with a special lamp socket after the conventional threaded lamp socket has been removed, which is very complicated and inconvenient.